Automobile vehicles commonly provide acoustic barriers between vehicle body members and the interior trim components of the vehicle. In addition to acoustic attenuation, these barriers when used between a door member and a door trim member of an automobile vehicle also provide a seal for moisture and dirt to prevent moisture or dirt from entering into the mechanical component areas of the door structure. In door applications when the barrier is affixed to a door trim member prior to assembly to the door assembly, such barriers are known as trim integrated acoustic shields (TIAS). Barriers which are formed of interpolymer materials are used to increase an acoustic attenuation across the barrier. Interpolymer materials are defined herein as compositions of polymeric material having one or more inorganic filler materials.
An example of an interpolymeric material acoustic barrier is provided in U.S. Pat. No. 5,409,779 issued to Puckett et al. on Apr. 25, 1995, the disclosure of which is incorporated herein by reference. The barrier formed in the Puckett reference is cold-formed and is effective for applications requiring a generally flat barrier where the flexible pocket formed by the cold-forming process is operable to expand into and seal an interior cavity of a door panel.
Improvements to known acoustic barriers are required, for example, in applications where complex geometry components and a complex seal area are present between a door structure and an interior trim panel. The interpolymer materials currently used in these applications may not provide sufficient porosity control when fabricated in a thermoforming operation. Where thermoformed or permanently formed pockets are desirable, an improved perimeter seal is also desirable in addition to the adhesive bead seal commonly used.